The invention relates to an electroacoustic apparatus having ringing signal generation means for generating a ringing signal composed of a combination of constituent signals and having an electroacoustic transducer which reproduces the ringing signal as a combination of ringing tones produced by the constituent signals.
An electroacoustic apparatus of the type defined hereinbefore has been put on the market as a so-called mobile telephone in a multitude of variants and is consequently known. In the known apparatus the constituent signals and, consequently, the ringing tones are always generated time sequentially, as a result of which the temporal sequence of ringing tones forms a combination of ringing tones, which combination of ringing tones forms a ringing event by means of which a user of the known apparatus is informed of an incoming call. The frequencies of the time-sequentially generated ringing tones correspond to a so-called piano scale. In other words, this means that the frequencies of the constituent signals, which are generated with the aid of the ringing signal generation means in order to generate the individual ringing tones and which in succession form the ringing signal, bear an irrational ratio to each other. For example, a first constituent signal may have a frequency f1=440.00 Hz, a second constituent signal may have a frequency of approximately f2=554.37 Hz, a third constituent signal may have a frequency of approximately f3=659.26 Hz and a fourth constituent signal may have a frequency of approximately f4=783.99 Hz. In the known apparatus this frequency relationship and the fact that always only constituent signals and, consequently, individual ringing tones are reproduced in temporal sequence result in a lowest frequency f1=440.00 Hz for the combination of reproduced ringing tones. During the acoustic reproduction of the combination of ringing tones, i.e. of the ringing event, this results in a tinny and cheap sound impression, which is not perceived as particularly attractive and pleasant by many users of the known apparatus.
It is an object of the invention to realize an improved apparatus of the type defined in the first paragraph with the aid of simple means and substantially without any additional means.
In order to achieve this object, characteristic features in accordance with the invention are provided in an electroacoustic apparatus in accordance with the invention, in such a manner that an electroacoustic apparatus in accordance with the invention can be characterized in the manner defined hereinafter, namely:
An electroacoustic transducer having ringing signal generation means for generating a ringing signal composed of a combination of constituent signals, and having an electroacoustic transducer, to which the ringing signal can be applied and which reproduces the ringing signal as a combination of ringing tones produced by the constituent signals, in which the ringing signal generation means include at least two fundamental tone signal generation means, which are each adapted to generate a fundamental tone signal of a given frequency, and in which the ringing signal generation means further include control means which serve for controllably activating the fundamental tone signal generation means and with the aid of which the fundamental tone signal generation means can be activated for a given time interval, and in which the fundamental tone signal generation means are adapted to generate fundamental tone signals of frequencies which are in a rational ratio to each other, and in which the control means are realized so as to cause a simultaneous activation of at least two fundamental tone signal generation means within a given time interval.
As a result of the provision of characteristic features in accordance with the invention it is achieved in a simple manner and substantially without any additional means that with the aid of the ringing signal generation means at least two constituent signals can be generated at the same time within a given time interval and, consequently, at least two ringing tones can be reproduced at the same time with the aid of the electroacoustic apparatus in accordance with the invention, as a result of which, owing to the fact that the frequencies of the constituent signals and, as a consequence, of the concurrent ringing tones bear a rational ratio to each other, a user perceives not only the at least two concurrent ringing tones but also at least one tone of a low frequency corresponding to the difference of the frequencies of the at least two concurrent ringing tones. Thus, it is achieved that a user of an electroacoustic apparatus in accordance with the invention not only hears the combination of ringing tones actually produced with the aid of the ringing signal generation means and of the electroacoustic transducer, which tones have comparatively high frequencies for ringing tones and lie in a frequency range between, for example, 440 Hz and, for example, 6 kHz, but also experiences a subjective bass perception, which on account of the subjective perception of ringing tones of lower frequencies results in the overall perception of the combination of ringing tones by a user being broadened to a frequency spectrum which is extended towards lower frequencies, which provides an improved ringing event.
In an electroacoustic apparatus in accordance with the invention it has proved to be very advantageous if, in addition, each fundamental tone signal generation means is adapted to generate at least one harmonic tone signal associated with the fundamental tone signal, while it has proved to be particularly advantageous if at least seven harmonic tone signals can be generated. The generation of harmonic tone signals and, consequently, of corresponding ringing tones makes it possible to generate a combination of ringing tones, which combination has the advantage that it is highly effectual to attract attention.
In the above context it has proved to be particularly advantageous if the additionally generated harmonic tone signal or the additionally generated harmonic tone signals have at least substantially the same amplitude as the associated fundamental tone signal. This makes it possible to realize a ringing tone combination which is experienced as very positive on account of its rich timbre.
The aforementioned aspects as well as further aspects of the invention will be apparent from the example of an embodiment described hereinafter and will be elucidated with the aid of this example.
The invention will be described in more detail hereinafter with reference to an embodiment which is shown in the drawing by way of example but to which the invention is not limited.